Showing papers by "Ulf Müller-Ladner published in 1998"
Journal Article•
TL;DR: The data indicate that cathepsin K is not only expressed by osteoclasts but also by synovial fibroblasts, and suggest that cathesin K contributes to bone destruction mediated by RAsynovial cells.
Abstract: Objective Cysteine proteinases B and L have been shown to be involved in matrix degradation of joints in patients with rheumatoid arthritis (RA) Since the cysteine proteinase cathepsin K is assumed to play a pivotal role in osteoclast mediated bone resorption, we investigated the expression of cathepsin K in RA joints Methods We studied 10 RA and 4 normal synovial specimens and 5 articular heads with RA lesions by in situ hybridization, applying specific riboprobes for cathepsin K, human collagen type I, and cathepsin B Antibodies against monocyte/macrophage associated CD68 antigen were applied in immunohistochemistry Reverse transcription-polymerase chain reaction (RT-PCR) and ribonuclease protection assay (RPA) were performed on 4 RA, 1 normal, and 1 immortalized normal fibroblast cultures Results Cathepsin K mRNA expression was upregulated in RA synovium compared to normal synovium Cathepsin K mRNA was expressed mainly by synovial fibroblasts These data were confirmed by RT-PCR and RPA In RA articular heads, cathepsin K mRNA was detected at sites where synovium attached and invaded underlying bone The cells at these sites represented collagen type I and cathepsin B mRNA expressing fibroblasts as well as CD68+ macrophages and giant cells In addition, a distinct expression of cathepsin K mRNA was also detected around lymphocytic infiltrates in RA synovium Conclusion The data indicate that cathepsin K is not only expressed by osteoclasts but also by synovial fibroblasts, and suggest that cathepsin K contributes to bone destruction mediated by RA synovial cells The expression of cathepsin K around lymphocytic infiltrates suggests further to facilitate the movement of mononuclear cells through the perivascular interstitial matrix and thereby contribute to interstitial matrix turnover
161 citations
TL;DR: Key issues in the review period addressing this interaction were hyperplasia of rheumatoid arthritis synovium, mechanisms of activation and cell cycle regulation ofsynovial fibroblasts, pathways of synovial attachment to cartilage and bone, and the regulation of matrix-degrading enzymes.
Abstract: Molecular biology has provided various new insights into the mechanisms operative in the pathogenesis of rheumatoid arthritis. Reflecting the unique character of rheumatoid synovium, advances have been achieved addressing the molecular changes taking place at the area of interaction between the aggr
73 citations
TL;DR: Current research in RA using state-of-the-art molecular biology techniques includes both the search for exogenous and endogenous retroviral gene sequences in synovium of patients with RA.
Abstract: There are several relationships between retroviruses and cellular transformation, as well as retroviruses being involved in the development of autoimmune diseases. Retroviruses have been discussed as etiologic agents modulating or triggering certain pathways in the pathogenesis of rheumatoid arthritis (RA). However, none of the currently known retroviruses has been identified as specific for RA. Due to the unique properties of retroviruses, distinct experimental approaches can be used to detect retroviral activity in cells and tissues. Current research in RA using state-of-the-art molecular biology techniques includes both the search for exogenous and endogenous retroviral gene sequences in synovium of patients with RA.
11 citations
TL;DR: Exensive synovectomy and arthrolysis in combination with an arthroplastic remodeling of both knee joints resulted in reduction of pain and joint effusion, therefore, synoveCTomy andArthroplastics remodeling might be a promising therapy to extend the period of time to prosthetic joint replacement in young patients with APL.
Abstract: Ein 22jahriger Patient mit Antiphospholipid-Antikorpersyndrom (APL) entwickelte ausgepragte Knochennekrosen an den Femurcondylen beider Kniegelenke. Durch Artikulosynovektomie mit ausgedehnter Arthrolyse und arthroplastischer Umformung an beiden Kniegelenken konnten zunehmende Kniegelenkbeschwerden sowie die persistierende Ergusbildung beseitigt werden. Auserdem erhoffen wir uns durch diese operative Masnahme einen deutlichen Zeitgewinn bis zur eventuell spater notwendigen endoprothetischen Versorgung des jungen Patienten.
2 citations